Helical should be your only option. You are shooting broadheads and need an arrow to spin. This means helical.
Arrow weight is a whole different issue and relates to spine. We need more information to give a realistic opinion. How many pounds do you pull, what type of cam is on your bow and what is your arrow length and draw length?
Vanes, generally a 4" vane. But with the new improved vanes like the blazer and quikspin, you can sometimes shoot the 2" versions. Your bow must be tuned very well to shoot the smaller ones and you need a really good flying broadhead.
For whitetails, you should get 50ft/lbs of kinetic energy or more. To calculate this, you need to know how fast your bow shoots a given arrow.
Then it is ke = mass weight in grains * (feet/sec ^2) / 450,240
To give you an example, my arrow weighs 400 grains and my bow shoots it at 274 feet per second. This calculates to 66.7 ft/lbs.
Give us more info and we will try to help.